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%I #9 Dec 24 2016 22:55:16
%S 48,180,245,432,500,605,931,980,1200,1280,1620,1805,2205,2352,2420,
%T 3380,3724,3888,3920,4500,4655,5445,5780,5808,6125,6845,7203,7220,
%U 7936,8112,8379,8405,8820,9072,9251,9680,10580,10800,11520,11760,12500
%N Numbers from A066112 that are neither square nor twice a square, i.e., are not in A028982 but are in A028983.
%H Harry J. Smith, <a href="/A066134/b066134.txt">Table of n, a(n) for n=1..1000</a>
%e 180 is neither square nor 2*square, but sigma_4(180)/sigma_2(180) = 1135275414/49686 = 22849 = 73*313.
%o (PARI) { n=0; for (m=1, 10^9, if (issquare(m) || issquare(m/2), next); if (frac(f=sigma(m, 4)/sigma(m, 2)), next); if (!isprime(f), write("b066134.txt", n++, " ", m); if (n==1000, return)) ) } \\ _Harry J. Smith_, Feb 02 2010
%Y Cf. A001157, A001159, A028982, A028983, A046871, A066109-A066112.
%K nonn
%O 1,1
%A _Labos Elemer_, Dec 06 2001
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